Complexes of cycloheptaamylose will be examined by X-ray crystallography in order to explain the observed enzyme-like activity of the cycloamyloses and their role as intermediates in chemical syntheses where they act to produce a stereochemical product. Structures of ion complexes of certain membrane active antibiotics will also be determined in order to correlate structure with membrane transport results. Hopefully this will lead to a better understanding of membrane function and the design of more specific ionophores.